chore(package): update grunt-eslint to version 18.1.0
chore(package): update grunt-eslint to version 18.1.0

http://greenkeeper.io/
mozilla/web-ext,shubheksha/web-ext,rpl/web-ext,shubheksha/web-ext,rpl/web-ext,kumar303/web-ext,mozilla/web-ext,kumar303/web-ext